1. Field of the Invention
The present invention relates to a device for restricting a movement of a sliding cover of a camera. The sliding cover is used to protect a photographing lens of the camera.
2. Description of the Related Art
Recently, so-called capsule-type cameras have been produced. Such a type of camera is usually provided with a sliding cover to protect a photographing lens from dirt or impact, when the photographing lens is in a retracted position; that is, when the camera is not being operated (or when a picture is not being taken). In addition, the portability of the camera can be improved, since the photographing lens is covered by the sliding cover.
When the sliding cover is slid to an opened position, the actuating switch (main switch of the camera) is turned ON and the photographing lens is advanced to a photographing position; that is, namely, the camera is capable of photographing. In this state, if the sliding cover is moved toward the closed position to cover the photographing lens, the actuating switch is turned OFF, and the photographing lens is moved to a retracted position. Accordingly, when the photographing lens is completely retracted, the sliding cover can be completely closed.
If a photographer attempts to close the sliding cover from the fully-opened state to the fully-closed state using an excessive force for a prolonged period of time, if the photographing lens is not completely retracted to the retracted position, the possibility exists that the sliding cover may interfere with the photographing lens. Since the sliding cover has to be moved by a predetermined toward the closed position in order to actuate the lens actuating motor, it is necessary to lock the sliding cover to prevent further movement before the photographing lens has completely retracted. The actuating force of the photographing lens during advancing or retracting thereof, is generally utilized for restricting a movement of the sliding cover.
A conventional sliding cover movement restricting device utilizing a locking pawl is known per se. In such a device, when the sliding cover is moved to the opened position, the locking pawl moves to a position capable of locking the sliding cover at the opened position, according to the advancement of the photographing lens. When the photographing lens is retracted, an actuating force is generated through forward and rearward movements of the photographing lens. The actuating force is then applied to the locking pawl via an interlocking device (e.g., a gear train). Accordingly, the locking pawl is moved to the locking release position which is in a direction opposite to the locking position.
With such a device, during a movement of the photographing lens from the photographing (operational) position to the retracted position, if a photographer mistakenly applies a strong force to the sliding cover in the closing direction, since the sliding cover is engaged with the locking pawl, the locking pawl is strongly pressed at the locking position. In such a state, if the photographing lens reaches the retracted position, the interlocking device applies an excessive force to the locking pawl which is in a fixed state. Therefore, the interlocking device, or the actuating system of the photographing lens, may receive the excessive force, and this may lead to damage or an operational error. In addition, once the sliding cover is opened, if the photographer mistakenly applies a force to close the sliding cover, the possibility exists that the photographing lens interferes with the sliding cover.